The previous chapter raised various methodological issues about the estimation of food supplies and the heights of past populations. This chapter introduces a number of tools that are useful in the evaluation of the nutritional status of populations in the past. The theoretical foundation for these tools is contained in Appendix A at the end of this chapter, which combines biological and economic variables into an integrated explanation of the physiological component of long-term economic development.

In this chapter, we consider several tools that can be used to reconstruct the historical interrelationship between biological and economic factors from patchy sources of data. Among these tools are energy cost accounting, the size distribution of calories, and Waaler curves and surfaces. The chapter concludes by evaluating some possible scenarios of the distribution of calories available for work in Britain circa 1800, which serve as examples of applications of our methodology.

Food consumption (diet) and energy cost accounting

Some studies of improvements in nutritional status and the correlated secular decline in mortality make the unfortunate implicit assumption that diet alone determines nutritional status. Epidemiologists and nutritionists, however, are careful to distinguish between these terms. Nutritional status denotes the balance between the intake of nutrients and the claims against it. It follows that an adequate level of nutrition is not determined solely by diet – the level of nutrient intake – but varies with individual circumstances.